The BBC talks to football fans about how the US has embraced the World Cup - and how US soccer culture still differs to that in other countries

Soccer - the sport the rest of the world calls a religion - is no longer a minority interest in the United States.

Analysis

Would USA success impact on the MLS?

"Absolutely. You can't say it is absolutely imperative to the growth of US soccer but it helps. Whether people at MLS or in US Soccer would want to admit it, the two things do have a distinct connection.

"If you are on Oklahoma, Nebraska, Idaho or Montana, you don't have professional soccer on your doorstep. All of a sudden it is on ESPN every day, in the newspapers and it starts to spark interest. People in those obscure areas might then ask 'do we have one of those leagues here? 'Yes, we do - the MLS'."

It is no longer, as one comedian put it, something mums pick their 12-year-old daughters up from.

United States soccer - or football depending on which side of the Atlantic you hail from - is on the brink of showing the world it has finally come of age.

The audience for regular-season games in the NFL in 2013 was 21m, although the Super Bowl was the most-watched programme in US history with 111.5m viewers.

This week Google searches for US Soccer outstripped NFL searches for only the second time in history, while Clint Dempsey's goal against Portugal is the second most tweeted moment of the World Cup so far with 305,000 tweets per minute.

"To have America watching these games is the 12th man for us," Dempsey said. "And in Brazil we feel like we have home field advantage.

Close encounter

At the airport, I bumped into a US fan called Mike D'Amico, writes Ben Smith. He is possibly the most famous American in Brazil. After Clint Dempsey scored the second against Portugal the TV pictures cut to a guy wearing a Teddy Roosevelt hat and screaming to the heavens. He went viral. He was stopped three times as he boarded the plane by fans who recognised him.

"Soccer has arrived in the US," D'Amico said. "None of what has happened to me would have been possible if there weren't enough eyeballs on that game. There is no way a picture of me making a stupid face, wearing a stupid hat goes viral unless there is a critical mass of people and there was."

"I remember games in the States where our opponents had more fans than us even though we were at home. Things are starting to change, that shows how far the game has come in the US."

At the heart of this surge in soccer's popularity is US head coach Jurgen Klinsmann.

As he prepares to face the country of his birth, the nation with whom he won the World Cup in 1990, he said the excitement in the US is hugely encouraging.

"We will give absolutely everything to beat Germany," he said. "You see the media attention growing, the internet and TV. That shows you where soccer is in the US."

Sunil Gulati, the president of US Soccer, agrees.

"Their response has been fantastic, whether it is viewing parties, media interest, viewing figures or the spontaneous eruptions from those walking down the street when we score a goal," he said. "It is everything that we dream about."

The American embassy in Brasilia estimates that close to 100,000 US citizens have travelled to Brazil for the tournament - three times more than any other country.

According to Fifa, US fans bought more tickets than those from every other country except the home nation.

The American Outlaws, a raucous US supporters group, chartered not one but three 737s to move fans. They sold all of the seats in the first week they were on sale.

"People are getting to know the players and being able to watch them live because of the time zones really helps," said Andy Wright, one of those US fans in Brazil.

And another, Travis Beardall, added: "Back home there is a fever growing and people are more inclined to watch games so there is something different about this year."

Grant Wahl, a senior writer for Sports Illustrated Magazine, believes it is crucial that the US capitalises on this.

"It is tremendously important they do that," Wahl said. "This really is US soccer coming of age and moving to a new level of consciousness in the United States.

United States' German connections

United States manager Jurgen Klinsmann may have been born in Germany but he is not the only member of the American squad with links to the European nation.

In total five US players were either born to American families in Germany or moved there as children.

Midfielder Jermaine Jones was born in Frankfurt and has said he will sing both anthems.

Fabian Johnson was born in Munich, Timmy Chandler in Frankfurt, John Brooks in Berlin and Julian Green moved to Germany at the age of two, having been born in Tampa.

All five come from military families and spent time on bases in Germany as children.

"It is part of what Klinsmann promised when he took over as head coach and it is a sign of how far things have come that there is a genuine feeling that the US will advance from what is the toughest group in the World Cup."

In Chicago, more than 20,000 fans flocked to Grant Park to watch the match with Portugal. The gates were closed 30 minutes before kick-off because it was full.

Over 20,000 fans turned up in Chicago to cheer on the United States in a park

In Orlando, Florida, thousands more packed into Wall Street Plaza, which has been renamed 'Soccer Central' for US matches.

"It's growing every minute," said former US goalkeeper Brad Friedel, who is working for BBC Radio 5 live at the World Cup.

"When we get results like against Ghana and Portugal it gives the sport a real lift. Now if we can somehow get through against Germany we are going to see that [big crowds] in 20 more cities across the United States.

"Those first two results were important as far as getting the average US supporter to get into the World Cup. If we had lost those the average supporter would have said 'we are going to lose to Germany, we're going out'.

TV audiences

After Germany, the US has been the second-biggest overseas television audience for the 2014 Fifa World Cup so far

"But by making a positive start we piqued interest in parts of the US that might not have been interested. As we did in 2002."